Phase-Resolved Wave Breaking Dissipation

相位分辨破波耗散

• 批准号: 1332719
• 负责人: James Thomson
• 金额: $ 70.86万
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-15 至 2018-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1332719&HistoricalAwards=false
• 关键词: Phase; Resolved; Wave; Breaking; Dissipation

The overall objective of this project is to understand ocean surface wave breaking, both in terms of the spectral input-dissipation balance that controls wave evolution and in terms of the fundamental physics at the air-sea interface. This proposal builds on recent success measuring wave breaking dissipation in the field, using newly developed SWIFT buoys and conventional video techniques. The investigation is guided by those results, in which short waves appear to saturate at high winds and in which the phase-averaged approach obscures the detailed relationship between turbulent kinetic energy dissipation and wave energy dissipation. New measurements will be made in the context of larger efforts at Ocean Weather Station P (OWS-P) and the pending Calwater2 experiment. The specific objectives are to: 1. Continue ongoing wave spectral observations at OWS-P in the North Pacific Ocean.2. Extend phase-averaged wave breaking dissipation measurements to higher wind speeds (greater than 15 m/s) using long-endurance versions of SWIFT buoys deployed throughout the winter months, and3. Develop methods for phase-resolved wave breaking dissipation measurements, using a combination of remote sensing (stereo video) and in situ (coherent arrays of SWIFT buoys) techniques.Wave breaking is a key process in wave evolution and air-sea interaction, yet is remains poorly understood. Wave forecast models, such as Wave Watch 3, use spectral parameterizations of breaking dissipation. These parameterizations are empirical and largely originate from laboratory studies, in which waves break as a result of superposition rather than the modulation instability process of real ocean waves. This study will measure wave breaking dissipation in the field and evaluate these parameterizations and the underlying hypothesis that wave breaking can be represented spectrally. This is directly related to the ongoing debate on the nature and magnitude of the "breaking strength" parameter b, which was successfully determined in laboratory studies but has ranged over four orders of magnitude in field studies.This effort will continue a unique time series, begun in 2010, of continuous wave spectral measurements at OWS-P. This is the only offshore wave buoy with spectral measurements in the Northwestern Pacific Ocean. This data is available in real-time and is used for maritime safety, wave forecast assimilation/calibration, and basic research. The data complement the upcoming installation of an Ocean Observatories Initiative (OOI) global node at OWS-P, which will not measure surface waves. The project will include the training of a PhD and of an undergraduate student. Outreach will include continued posts (by invitation) to the New York Times "Scientists at Work" blog, annual participation in the Pacific Science Center's "Science EXPO", and continued participation in the Ocean Inquiry Project.

该项目的总体目标是了解海洋表面波浪破碎，无论是在控制波浪演变的光谱输入耗散平衡方面，还是在海气界面的基本物理学方面。该建议建立在最近成功测量波浪破碎耗散领域，使用新开发的SWIFT浮标和传统的视频技术。调查的指导下，在这些结果中，短波出现饱和，在大风和相位平均的方法模糊了湍流动能耗散和波能耗散之间的详细关系。新的测量将在海洋气象站P（OWS-P）和即将进行的Calwater 2实验的更大努力的背景下进行。具体目标是：1.继续在北太平洋OWS-P进行波谱观测。使用在整个冬季部署的长寿命SWIFT浮标，将相位平均波浪破碎耗散测量扩展到更高的风速（大于15 m/s），以及3。结合使用遥感（立体视频）和现场（SWIFT浮标相干阵列）技术，开发相位分辨的波浪破碎耗散测量方法波浪破碎是波浪演变和海气相互作用的一个关键过程，但人们对此仍知之甚少。波浪预报模型，如Wave Watch 3，使用破碎耗散的谱参数化。这些参数化是经验性的，主要来源于实验室研究，其中波浪破碎是叠加的结果，而不是真实的海浪的调制不稳定过程。本研究将测量波浪破碎耗散在现场和评估这些参数化和基本的假设，波浪破碎可以表示频谱。这与正在进行的关于“断裂强度”参数B的性质和大小的辩论直接相关，该参数在实验室研究中成功确定，但在现场研究中已经超过四个数量级。这是西北太平洋唯一具有光谱测量的近海波浪浮标。这些数据是实时可用的，用于海上安全，波浪预报同化/校准和基础研究。这些数据补充了即将在OWS-P安装的海洋观测站倡议（OOI）全球节点，该节点将不测量表面波。该项目将包括培训一名博士和一名本科生。外联活动将包括继续（应邀）在《纽约》“工作中的科学家”博客上发帖，每年参加太平洋科学中心的“科学博览会”，并继续参加海洋调查项目。